Development of a general synthetic strategy to the P. elisabethae diterpenes: Total synthesis of (+)-erogorgiaene

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C-H functionalization by means of rhodium carbenoid induced C-H insertion provides new strategies for the construction of C-C bonds. The success of this methodology is attributed to the combination of the donor/acceptor-substituted carbenoids and the dirhodium tetraprolinate catalysts. The first chapter of this thesis explores the use of thiophene as a potential electron-donor on the rhodium carbenoid for intermolecular C-H activation reactions. From these studies a short synthesis of the K + channel blocker (+)-cetiedil was completed. The second chapter focuses on the development of the dirhodium tetraprolinate catalysts as solid supported reagents. This methodology has been extended to a range of electronically and structurally diverse dirhodium complexes, and represents a universal strategy for the immobilization of chiral dirhodium catalysts. The last chapter describes a general synthetic strategy to the P. elisabethae diterpenes illustrated by the total synthesis of (+)-erogorgiaene. The key step features the combined C-H activation/Cope rearrangement reaction of racemic dihydronaphthalenes, which engage in enantiodivergent reaction pathways. This reaction forms the three main chiral centers common to most of the P. elisabethae diterpenes, in a highly stereoselective manner.